This invention relates to vibratory rotation sensors, and more particularly to a sensor of the "vibrating bell" type referred to as a sonic gyro.
Sonic gyros are disclosed in U.S. Pat. Nos. 3,625,067; 3,656,354; 3,678,762; 3,719,074 and 4,157,041. This type of gyro is also disclosed in "The HRG: A new low-noise interial rotation sensor". PROC. 16th JT. SERVICES DATA EXCHANGE FOR INERTIAL SYSTEMS, Los Angeles, Calif., Nov. 16-18, 1982 by E. J. Loper and D. D. Lynch and in IEEE Transactions on Aerospace and Electronics Systems Vol. AES-20 No. 4, July, 1984.
The gyro consists of three principal fused quartz parts, a forcer, a hemispherical resonator and a pick-off, joined together with indium and enclosed in a vacuum metal housing.